There are many times where recording data over a longer
period of time is required in order to get the job done. In
various projects I've used many methods to accomplish this -
network sniffers, serial port data monitors, network SNMP data
logging software, custom written software to repeatedly ask
network equipment for ARP tables, a video camera to catch a
screen that flashes by too quickly to read, and a whole host of
other items. In each case, that historical data always proved
key in isolating a given problem.

In my personal arsenal of weapons to wield against issues,
one has always eluded me - the data recording digital multimeter.
Whenever I needed one, there was always one available at the
company I worked for and it was utilized. But now I needed my
own.

Digging around I found many options - most all of them were
north of $150 with some - the Greenlee DMSC-9 which is just the
interface kit for the DM-860 DMM - that kit alone goes for $120!
That isn't the meter, that is just the kit that allows the meter
to push its data out the port!

Reading all that, and doing more research, eventually I came
across the TekPower TP4000ZC PC Based RS232-Interfaced Auto
Ranging Digital Multimeter.

I love the Internet! It is so easy to get information
from others about what is good and bad about any given product now - you
use to have to subscribe to Consumer Reports and hope they review your
item or know someone else that bought the same product. Nowadays, people
are so free to share their opinions online you can learn most everything
you need in a few minutes of searching and reading.

If you read those reviews, not many people had good
things to say about the included software. Few were able to get it to
work.

When mine arrive, I tried as well and could get it to
work once per reboot, and then it wouldn't read any data anymore. This
is a shot of the screen:

The digital and analog buttons on the right blank out
the upper and lower meter sections. List brings up a list of sampled
points, graph brings up a simple graph. I wasn't able to get it to work
long enough to try the sample recording functions, so I can't speak to
those. I did some poking around and it looks like it was written in
Visual Basic 6.0 and not updated for any of the newer operating systems,
which likely explains everyone's issues.

Plus, it has the standard "COM1" through "COM4" port
selections, and often times external serial port devices get pushed
above those standard locations.

But I really like the visual appearance of the analog
meter! But then again, I started playing with electronics back in 1971
at the ripe old age of 8. We didn't have digital meters back then. I
wouldn't discover computers for another 4 years.

Ok, boring
backstory - get to the point already!

I'm writing my own data logging meter application
program for this meter. It will work with other meters that have the
same protocol, and I know others exist that do - and can likely be
adapted pretty easily for meters with different protocols, but that
isn't my first goal.

In software engineering, first make it work. Then make
it work [better, faster, easier, whizzier, ...]

My needs are:

Standard CSV / Text that imports into Excel easily
Regular sample period, dynamically adjustable by the GUI
Ability to record delta-samples VS just doing fixed time intervals
Auto-adjust to whatever the meter is set to
Work with modern Windows operating systems - so built in Visual Studio
32 or 64 bit compatible
Average multiple samples to smooth out erratic data

I'm using it right now and have been for a couple of
days, and as I use it I'm throwing in functions that make it nicer. For
example, I found that while gathering data I was writing in my notebook
when I was doing certain things so I could see later in the log file
what happened to my experiment and could correlate by timestamp to the
event. After about the 5th time, I thought to myself "This is silly -
the log file should contain my notes along with the timestamp whenever I
want to add a note!" so I stopped, spent 5 minutes, and added that
feature. No more paper notes!

In another case, I forgot to check my little checkbox to
turn logging on and had to re-do a two hour test. So now I'm changing
the color of the log file path textbox to be green when you are logging
and red when you are not logging - so much more "IN YOUR FACE" than just
the little checkbox.

In the end, I think I'm going to end up with quite a
nice little data logging application. And since others seem to be
complaining about the software that comes with the meter, I think others
can use it as well.

Beta
testers anyone?

4/2016: This will be a commercial software product. The
beta is over. Next step will be a kickstarter project to fund
development of some enhancements that are kind of important before
letting it out for public consumption. There is a ton of work that
still has to be done - for example, I know that if you are logging to a
data file on a remote network share and that share becomes unavailable,
the code will crash. Error detection and recovery is often times more
coding than the actual main purpose of a software module as there are
always more ways things can go wrong than go right. The core
functionality is done as I've been using it to record data for
another project (and article) and
I'm throwing this up on the web and will hopefully see it indexed in the
next couple of weeks.

If you are interested, send me an email and I'll be sure
to let you know when the kickstarter goes live. Send me an email request to: